refactor to eliminate duplicated JSON parsing logic (#4150)

1 files changed, 20 insertions, 289 deletions

diff --git a/src/exchange/taler-exchange-httpd_parsing.h b/src/exchange/taler-exchange-httpd_parsing.h
index a39235685..d09f58767 100644
--- a/src/exchange/taler-exchange-httpd_parsing.h
+++ b/src/exchange/taler-exchange-httpd_parsing.h
@@ -1,6 +1,6 @@
 /*
   This file is part of TALER
-  Copyright (C) 2014, 2015 GNUnet e.V.
+  Copyright (C) 2014, 2015, 2016 GNUnet e.V.
 
   TALER is free software; you can redistribute it and/or modify it under the
   terms of the GNU Affero General Public License as published by the Free Software
@@ -26,6 +26,7 @@
 #include <microhttpd.h>
 #include <jansson.h>
 #include "taler_util.h"
+#include "taler_json_lib.h"
 
 
 /**
@@ -72,291 +73,45 @@ TMH_PARSE_post_cleanup_callback (void *con_cls);
 
 
 /**
- * Constants for JSON navigation description.
- */
-enum TMH_PARSE_JsonNavigationCommand
-{
-  /**
-   * Access a field.
-   * Param: const char *
-   */
-  TMH_PARSE_JNC_FIELD,
-
-  /**
-   * Access an array index.
-   * Param: int
-   */
-  TMH_PARSE_JNC_INDEX,
-
-  /**
-   * Return base32crockford encoded data of
-   * constant size.
-   * Params: (void *, size_t)
-   */
-  TMH_PARSE_JNC_RET_DATA,
-
-  /**
-   * Return base32crockford encoded data of
-   * variable size.
-   * Params: (void **, size_t *)
-   */
-  TMH_PARSE_JNC_RET_DATA_VAR,
-
-  /**
-   * Return a json object, which must be
-   * of the given type (JSON_* type constants,
-   * or -1 for any type).
-   * Params: (int, json_t **)
-   */
-  TMH_PARSE_JNC_RET_TYPED_JSON,
-
-  /**
-   * Return a `struct GNUNET_CRYPTO_rsa_PublicKey` which was
-   * encoded as variable-size base32crockford encoded data.
-   */
-  TMH_PARSE_JNC_RET_RSA_PUBLIC_KEY,
-
-  /**
-   * Return a `struct GNUNET_CRYPTO_rsa_Signature` which was
-   * encoded as variable-size base32crockford encoded data.
-   */
-  TMH_PARSE_JNC_RET_RSA_SIGNATURE,
-
-  /**
-   * Return a `struct TALER_Amount` which was
-   * encoded within its own json object.
-   */
-  TMH_PARSE_JNC_RET_AMOUNT,
-
-  /**
-   * Return a `struct GNUNET_TIME_Absolute` which was
-   * encoded within its own json object.
-   * Param: struct GNUNET_TIME_Absolute *
-   */
-  TMH_PARSE_JNC_RET_TIME_ABSOLUTE,
-
-  /**
-   * Return a `uint64_t` which was
-   * encoded as a JSON integer.
-   * Param: uint64_t *
-   */
-  TMH_PARSE_JNC_RET_UINT64
-
-};
-
-
-/**
- * Navigate through a JSON tree.
- *
- * Sends an error response if navigation is impossible (i.e.
- * the JSON object is invalid)
+ * Parse JSON object into components based on the given field
+ * specification.
  *
  * @param connection the connection to send an error response to
  * @param root the JSON node to start the navigation at.
- * @param ... navigation specification (see `enum TMH_PARSE_JsonNavigationCommand`)
+ * @param spec field specification for the parser
  * @return
- *    #GNUNET_YES if navigation was successful
+ *    #GNUNET_YES if navigation was successful (caller is responsible
+ *                for freeing allocated variable-size data using
+ *                #GNUNET_JSON_parse_free() when done)
  *    #GNUNET_NO if json is malformed, error response was generated
  *    #GNUNET_SYSERR on internal error
  */
 int
-TMH_PARSE_navigate_json (struct MHD_Connection *connection,
-                         const json_t *root,
-                         ...);
-
-
-/**
- * @brief Specification for how to parse a JSON field.
- */
-struct TMH_PARSE_FieldSpecification
-{
-  /**
-   * Name of the field.  NULL only to terminate array.
-   */
-  const char *field_name;
-
-  /**
-   * Where to store the result.  Must have exactly
-   * @e destination_size bytes, except if @e destination_size is zero.
-   * NULL to skip assignment (but check presence of the value).
-   */
-  void *destination;
-
-  /**
-   * How big should the result be, 0 for variable size.  In
-   * this case, @e destination must be a "void **", pointing
-   * to a location that is currently NULL and is to be allocated.
-   */
-  size_t destination_size_in;
-
-  /**
-   * @e destination_size_out will then be set to the size of the
-   * value that was stored in @e destination (useful for
-   * variable-size allocations).
-   */
-  size_t *destination_size_out;
-
-  /**
-   * Navigation command to use to extract the value.  Note that
-   * #TMH_PARSE_JNC_RET_DATA or #TMH_PARSE_JNC_RET_DATA_VAR must be used for @e
-   * destination_size_in and @e destination_size_out to have a
-   * meaning.  #TMH_PARSE_JNC_FIELD and #TMH_PARSE_JNC_INDEX must not be used here!
-   */
-  enum TMH_PARSE_JsonNavigationCommand command;
-
-  /**
-   * JSON type to use, only meaningful in connection with a @e command
-   * value of #TMH_PARSE_JNC_RET_TYPED_JSON.  Typical values are
-   * #JSON_ARRAY and #JSON_OBJECT.
-   */
-  int type;
-
-};
+TMH_PARSE_json_data (struct MHD_Connection *connection,
+                     const json_t *root,
+                     struct GNUNET_JSON_Specification *spec);
 
 
 /**
- * Parse JSON object into components based on the given field
- * specification.
+ * Parse JSON array into components based on the given field
+ * specification.  Generates error response on parse errors.
  *
  * @param connection the connection to send an error response to
  * @param root the JSON node to start the navigation at.
- * @param spec field specification for the parser
+ * @param[in,out] spec field specification for the parser
+ * @param ... -1-terminated list of array offsets of type 'int'
  * @return
  *    #GNUNET_YES if navigation was successful (caller is responsible
  *                for freeing allocated variable-size data using
- *                #TMH_PARSE_release_data() when done)
+ *                #GNUNET_JSON_parse_free() when done)
  *    #GNUNET_NO if json is malformed, error response was generated
  *    #GNUNET_SYSERR on internal error
  */
 int
-TMH_PARSE_json_data (struct MHD_Connection *connection,
-                     const json_t *root,
-                     struct TMH_PARSE_FieldSpecification *spec);
-
-
-/**
- * Release all memory allocated for the variable-size fields in
- * the parser specification.
- *
- * @param spec specification to free
- */
-void
-TMH_PARSE_release_data (struct TMH_PARSE_FieldSpecification *spec);
-
-
-/**
- * Generate line in parser specification for fixed-size value.
- *
- * @param field name of the field
- * @param value where to store the value
- */
-#define TMH_PARSE_member_fixed(field,value) { field, value, sizeof (*value), NULL, TMH_PARSE_JNC_RET_DATA, 0 }
-
-
-/**
- * Generate line in parser specification for variable-size value.
- *
- * @param field name of the field
- * @param[out] ptr pointer to initialize
- * @param[out] ptr_size size to initialize
- * @return corresponding field spec
- */
-struct TMH_PARSE_FieldSpecification
-TMH_PARSE_member_variable (const char *field,
-                           void **ptr,
-                           size_t *ptr_size);
-
-
-/**
- * Generate line in parser specification for 64-bit integer
- * given as an integer in JSON.
- *
- * @param field name of the field
- * @param[out] u64 integer to initialize
- * @return corresponding field spec
- */
-struct TMH_PARSE_FieldSpecification
-TMH_PARSE_member_uint64 (const char *field,
-                         uint64_t *u64);
-
-
-/**
- * Generate line in parser specification for JSON array value.
- *
- * @param field name of the field
- * @param[out] jsonp address of JSON pointer to initialize
- * @return corresponding field spec
- */
-struct TMH_PARSE_FieldSpecification
-TMH_PARSE_member_array (const char *field,
-                        json_t **jsonp);
-
-
-/**
- * Generate line in parser specification for JSON object value.
- *
- * @param field name of the field
- * @param[out] jsonp address of pointer to JSON to initialize
- * @return corresponding field spec
- */
-struct TMH_PARSE_FieldSpecification
-TMH_PARSE_member_object (const char *field,
-                         json_t **jsonp);
-
-
-/**
- * Generate line in parser specification for RSA public key.
- *
- * @param field name of the field
- * @param[out] pk key to initialize
- * @return corresponding field spec
- */
-struct TMH_PARSE_FieldSpecification
-TMH_PARSE_member_denomination_public_key (const char *field,
-                                          struct TALER_DenominationPublicKey *pk);
-
-
-/**
- * Generate line in parser specification for RSA public key.
- *
- * @param field name of the field
- * @param sig the signature to initialize
- * @return corresponding field spec
- */
-struct TMH_PARSE_FieldSpecification
-TMH_PARSE_member_denomination_signature (const char *field,
-                                         struct TALER_DenominationSignature *sig);
-
-
-/**
- * Generate line in parser specification for an amount.
- *
- * @param field name of the field
- * @param[out] amount a `struct TALER_Amount *` to initialize
- * @return corresponding field spec
- */
-struct TMH_PARSE_FieldSpecification
-TMH_PARSE_member_amount (const char *field,
-                         struct TALER_Amount *amount);
-
-
-/**
- * Generate line in parser specification for an absolute time.
- *
- * @param field name of the field
- * @param[out] atime time to initialize
- * @return corresponding field spec
- */
-struct TMH_PARSE_FieldSpecification
-TMH_PARSE_member_time_abs (const char *field,
-                           struct GNUNET_TIME_Absolute *atime);
-
-
-
-/**
- * Generate line in parser specification indicating the end of the spec.
- */
-#define TMH_PARSE_MEMBER_END { NULL, NULL, 0, NULL, TMH_PARSE_JNC_FIELD, 0 }
+TMH_PARSE_json_array (struct MHD_Connection *connection,
+                      const json_t *root,
+                      struct GNUNET_JSON_Specification *spec,
+                      ...);
 
 
 /**
@@ -381,28 +136,4 @@ TMH_PARSE_mhd_request_arg_data (struct MHD_Connection *connection,
                                 size_t out_size);
 
 
-/**
- * Extraxt variable-size base32crockford encoded data from request.
- *
- * Queues an error response to the connection if the parameter is missing
- * or the encoding is invalid.
- *
- * @param connection the MHD connection
- * @param param_name the name of the parameter with the key
- * @param[out] out_data pointer to allocate buffer and store the result
- * @param[out] out_size set to the size of the buffer allocated in @a out_data
- * @return
- *   #GNUNET_YES if the the argument is present
- *   #GNUNET_NO if the argument is absent or malformed
- *   #GNUNET_SYSERR on internal error (error response could not be sent)
- */
-int
-TMH_PARSE_mhd_request_var_arg_data (struct MHD_Connection *connection,
-                                    const char *param_name,
-                                    void **out_data,
-                                    size_t *out_size);
-
-
-
-
 #endif /* TALER_EXCHANGE_HTTPD_PARSING_H */